[c-nsp] Same IP on two interfaces?

[Jeff Kell]

Afsheen Bigdeli wrote:
> Hi,
>
> You may want to investigate HSRP or GLBP for this depending your needs. 
> (It sounds like HSRP would do the trick nicely for you, and it's very 
> easy to configure and troubleshoot - downside for both solutions is that 
> you'd need three IP addresses, one for the VIP and one real address for 
> each interface.)
I *think* this is the ticket, except that the router can't have two
interfaces (the two IPs) on the same subnet, but since you are
connecting to two different switches in your scenario, they can
certainly fulfill the need.

Someone suggested etherchannel... but you can't etherchannel across
switches (unless you have something like a stacking 3750 that is really
one logical chassis); in that case you use SVIs on both ends and use the
two interfaces as L2 switchports.  It would work with an SVI on both
ends and letting spanning tree activate one link or the other.

HSRP/GLBP with the SVI in the router and numbered HSRP/GLBP interfaces
on the switches should do this nicely.

Jeff